Timing of BBL subroutine

Context

The execution time of subroutine bbl (computation of bottom-boundary-layer transport coefficients) is not reported in the timing.output file, both in NEMO v4.2.2 and in NEMO main.

Analysis

Subroutine bbl of module trabbl is called directly from the time-step control procedure. It, however, does not include explicit timing instructions and therefore its execution time is added to that of the time-step control procedure (stp, stp_MLF, or stp_RK3).

Fix

Timer start and stop instructions should be added to subroutine bbl of module trabbl with an appropriate label (bbl).